Very interesting find.
I had 3.13 Bios and updated to 3.14. I noticed an improvement. I was told that one change was support for Southbridge 450. (This MB has 400 from what I can tell)
When I updated my ATI X700 to 7.2 of ATI's Catalist drivers, it added ATI southbridge drivers. With 6.8,6.9,7.0 and 7.1 never installed anything called Southbridge. It appears that 3.14 fixed something in SB that now ATI works correctly with it?